Display device having a bending area

ABSTRACT

A display device includes a substrate including a bending area located between a first area and a second area. The substrate is bent in relation to a bending axis. A first wiring unit including a plurality of first wirings is arranged on the substrate to sequentially extend over the first area, the bending area, and the second area. First central axes included in each of the plurality of first wirings are spaced apart from each other by a first pitch in the bending area. A second wiring unit including a plurality of second wirings is arranged on the substrate to sequentially extend over the first area, the bending area, and the second area. Second central axes included in each of the plurality of second wirings are spaced apart from each other by a second pitch greater than the first pitch in the bending area.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of U.S. patent application Ser. No.16/573,601, filed on Sep. 17, 2019, which is a Continuation of U.S.patent application Ser. No. 15/467,088, filed on Mar. 23, 2017, now U.S.Pat. No. 10,424,631, issued on Sep. 24, 2019, which claims priorityunder 35 U.S.C. § 119 to Korean Patent Application No. 10-2016-0039524,filed on Mar. 31, 2016, in the Korean Intellectual Property Office, thedisclosures of which are incorporated by reference herein in theirentirety.

1. TECHNICAL FIELD

Exemplary embodiments of the present invention relate to a displaydevice, and more particularly, to a display device having a bendingarea.

2. DISCUSSION OF RELATED ART

In general, a display device may include a display over a substrate.Such a display device may be bent at least partially, thus increasingvisibility from various angles or reducing an area of a non-displayarea.

SUMMARY

One or more exemplary embodiments of the present invention include adisplay device, which may reduce or eliminate an occurrence of defects,such as a disconnection, during manufacturing of the display devicewhile increasing a lifespan of the display device. However, exemplaryembodiments of the present invention are not limited thereto.

According to one or more exemplary embodiments of the present invention,a display device includes a substrate including a bending area locatedbetween a first area and a second area. The substrate is bent inrelation to a bending axis. A first wiring unit including a plurality offirst wirings is arranged on the substrate to sequentially extend overthe first area, the bending area, and the second area. First centralaxes included in each of the plurality of first wirings are spaced apartfrom each other by a first pitch in the bending area. A second wiringunit including a plurality of second wirings is arranged on thesubstrate to sequentially extend over the first area, the bending area,and the second area. Second central axes included in each of theplurality of second wirings are spaced apart from each other by a secondpitch greater than the first pitch in the bending area.

The plurality of first wirings and the plurality of second wirings maybe substantially parallel with each other.

The plurality of first wirings and the plurality of second wirings mayextend in a direction crossing the bending axis.

The second pitch may be n times as wide as the first pitch, n≥2, and nmay be a natural number.

The second pitch may at least two times as wide as the first pitch.

The plurality of respective second central axes of the plurality ofsecond wirings may be spaced apart from each other by a pitch narrowerthan the second pitch in the first area and the second area.

Each of the plurality of first wirings may have a first width, and eachof the plurality of second wirings may have a second width greater thanthe first width.

Facing edges of each of the plurality of first wirings may be spacedapart from each other by a first distance, and facing edges of each ofthe plurality of second wirings may be spaced apart from each other by asecond distance that is substantially the same as the first distance.

Each of the plurality of second wirings may include a first sub wiringand a second sub wiring that are spaced apart from each other by apredetermined distance. The first sub wiring and the second sub wiringmay be electrically connected to each other.

Facing edges of each of the plurality of first wirings may be spacedapart from each other by a first distance, and facing edges of each ofthe plurality of second wirings may be spaced apart from each other by asecond distance that is substantially the same as the first distance.

Each of the second wirings of the plurality of second wirings may besymmetrical to each other with respect to each of the plurality ofsecond central axes.

The first sub wiring and the second sub wiring may be connected inparallel to each other.

Each of the plurality of second wirings may further include a third subwiring spaced apart from the second sub wiring by a predetermineddistance. The second sub wiring and the third sub wiring may beelectrically connected to each other.

Resistance of each of the plurality of second wirings may be lower thanresistance of each of the plurality of first wirings.

The display device may further include a pad unit located over thesecond area of the substrate.

The display device may include a display disposed over the substrate;and a driver disposed around the display and driving the display. Thefirst wiring unit may be a data wiring unit providing a data signal tothe display, and the second wiring unit may be a wiring unit supplyingpower to the driver or the display.

The display may be over the first area of the substrate.

The display device may include a thin film transistor disposed over thefirst area or the second area of the substrate and including a sourceelectrode, a drain electrode, and a gate electrode. The first wiringunit may include a first conductive layer in the bending area and asecond conductive layer in the first area and the second area. The firstconductive layer may include a same material as the source electrode orthe drain electrode, and the second conductive layer may include a samematerial as the gate electrode.

The first conductive layer and the second conductive layer may beelectrically connected to each other via a contact hole.

The display device may include a thin film transistor disposed over thefirst area or the second area of the substrate and including a sourceelectrode, a drain electrode, and a gate electrode. The second wiringunit may include a third conductive layer over the first area, thebending area, and the second area. The third conductive layer may beover the same layer as the source electrode or the drain electrode.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present invention will become moreapparent by describing in detail exemplary embodiments thereof, withreference to the accompanying drawings, in which:

FIG. 1 is a schematic perspective view of a display device according toan exemplary embodiment of the present invention;

FIG. 2 is a schematic plan view of the display device of FIG. 1 that isnot bent;

FIG. 3 is a schematic enlarged plan view of a part of the display deviceof FIG. 1;

FIG. 4 is a schematic enlarged plan view of a part of a display deviceaccording to another exemplary embodiment of the present invention;

FIG. 5 is a schematic enlarged plan view of a part of a display deviceaccording to another exemplary embodiment of the present invention;

FIG. 6 is a schematic enlarged plan view of a part of a display deviceaccording to another exemplary embodiment of the present invention;

FIG. 7 is a cross-sectional view of a part of the display device of FIG.1;

FIG. 8 is a schematic plan view of a part of the display device of FIG.1;

FIG. 9 is a schematic cross-sectional view taken along a line A-A ofFIG. 8;

FIG. 10 is a schematic cross-sectional view of a part of a displaydevice according to another exemplary embodiment of the presentinvention;

FIG. 11 is a schematic cross-sectional view of a part of a displaydevice according to another exemplary embodiment of the presentinvention; and

FIG. 12 is a graph showing bending of a display device according to anexemplary embodiment of the present invention.

DETAILED DESCRIPTION

Exemplary embodiments of the present invention will be described belowin more detail with reference to the accompanying drawings. In thisregard, the exemplary embodiments may have different forms and shouldnot be construed as being limited to the exemplary embodiments of thepresent invention described herein.

Like reference numerals may refer to like elements throughout thespecification and drawings.

It will be understood that although the terms “first” and “second” maybe used herein to describe various components, these components shouldnot be limited by these terms.

Sizes of elements in the drawings may be exaggerated for clarity ofdescription.

According to some exemplary embodiments of the present invention, thex-axis, the y-axis and the z-axis are not limited to three axes of therectangular coordinate system, and may be interpreted in a broadersense. For example, the x-axis, the y-axis, and the z-axis may beperpendicular to each other, or may represent different directions thatare not perpendicular to each other.

FIG. 1 is a schematic perspective view of a display device according toan embodiment exemplary embodiment of the present invention. FIG. 2 is aschematic plan view of the display device of FIG. 1 that is not bent.

A substrate 100 that is a part of the display device may be partiallybent so that the display device has a partially bent shape. However, forclarity of description, FIG. 2 illustrates the display device that isnot bent. Exemplary embodiments of the present invention described belowin more detail with reference to FIGS. 2-11 may refer to the displaydevice that is not bent.

Referring to FIGS. 1 and 2, the substrate 100 included in the displaydevice may have a bending area BA extending in one direction (e.g., a +xdirection). The bending area BA may be positioned between a first area1A and a second area 2A in another direction (e.g., a +y direction) thatintersects with the one direction (e.g., the +x direction). Referring toFIG. 1, the substrate 100 may be bent with respect to a bending axis BAXextending in the one direction (e.g., the +x direction).

The substrate 100 may include various materials having flexible orbendable characteristics. For example, the substrate 100 may include apolymer resin, such as polyethersulphone (PES), polyacrylate (PAR),polyetherimide (PEI), polyethylene naphthalate (PEN), polyethyleneterephthalate (PET), polyphenylene sulfide (PPS), polyallylate,polyimide (PI), polycarbonate (PC), or cellulose acetate propionate(CAP).

The first area 1A may include a display area DA. Referring to FIG. 2,the first area 1A may include a part of a non-display area NDA outsidethe display area DA. The second area 2A may also include the non-displayarea NDA.

A display 200 may be disposed in the display area DA of the first area1A. The display 200 may include a display device 250 and may display animage by controlling the display device 250 to emit light. A structureof the display 200 will be described below in more detail with referenceto FIG. 7.

A first wiring unit 300 and a second wring unit 400 may be disposed overthe substrate 100. The first wiring unit 300 and the second wiring unit400 may be positioned over the non-display area NDA outside the displayarea DA, and may be sequentially disposed over the first area 1A, thesecond area 2A, and the bending area BA. At least a part of each of thefirst wiring unit 300 and the second wiring unit 400 may overlap withthe bending area BA. Each of the first wiring unit 300 and the secondwring unit 400 may be electrically connected to the display 200.

The first wiring unit 300 may be a wiring unit that transmits a datasignal to the display 200. For example, the first wiring unit 300 may bea data line. The second wiring unit 400 may be spaced apart from thefirst wiring unit 300. The second wiring unit 400 may include a firstpower wiring unit 410 and a second power wiring unit 420 that supplydriving power to the display 200, and a driving circuit wiring unit 430applying a signal to a scan driving circuit 530. The first power wiringunit 410 and the second power wiring unit 420 may be referred to as adriver, and may drive the display. The scan driving circuit 530 may be ashift register. For example, the first power wiring unit 410 may be anELVDD line, the second power wiring unit 420 may be an ELVSS line, andthe driving circuit wiring unit 430 may be a scan line or a gate line.

Although the first wiring unit 300 and the first power wiring unit 410of the second wiring unit 400 overlap with each other in the first area1A in FIG. 2, the first wiring unit 300 and the first power wiring unit410 of the second wiring unit 400 might not be electrically connected toeach other. The first wiring unit 300 and the first power wiring unit410 of the second wiring unit 400 may be separate layers in the firstarea 1A. The second wiring unit 400 may be formed over substantially theentire area of the substrate 100 and may include a same material as asource electrode 206 a or a drain electrode 206 b of a thin filmtransistor TFT that will be described in more detail below. The firstwiring unit 300 may include a same material as a gate electrode 202 ofthe thin film transistor TFT disposed in the first area 1A and thesecond area 2A. The first wiring unit 300 may include a same material asthe source electrode 206 a or the drain electrode 206 b of the thin filmtransistor TFT disposed in the bending area BA. Thus, layers of thefirst wiring unit 300 and the first power wiring unit 410 of the secondwiring unit 400 may overlap each other in the first area 1A withoutbeing electrically connected to each other.

According to an exemplary embodiment of the present invention, the firstwiring unit 300 and the second wring unit 400 may include one or moremetals selected from molybdenum (Mo), aluminum (Al), platinum (Pt),palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni),neodymium (Nd), iridium (Ir), chrome (Cr), calcium (Ca), titanium (Ti),tungsten (W), and copper (Cu). Each of the first wiring unit 300 and thesecond wring unit 400 may have a single-layered or multi-layeredstructure.

A pad unit 500 may overhang an edge of the substrate 100. A separatechip may be attached to the pad unit 500. The pad unit 500 may include afirst pad unit 510 and a second pad unit 520. The first wiring unit 300may be connected to the first pad unit 510, and the second wiring unit400 may be connected to the second pad unit 520. A signal applied to thepad unit 500 may be provided to the display 200.

According to an exemplary embodiment of the present invention, the firstwiring unit 300 may include a plurality of first wirings 300-1, 300-2, .. . (see, e.g., FIG. 3) that may be disposed over the substrate 100 tosequentially extend over the first area 1A, the bending area BA, and thesecond area 2A of the substrate 100. The plurality of first wirings300-1, 300-2, . . . may be spaced apart from each other by apredetermined space.

The second wiring unit 400 may include a plurality of second wirings400-1, 400-2, . . . (see, e.g., FIG. 3) that may be disposed over thesubstrate 100 to sequentially extend over the first area 1A, the bendingarea BA, and the second area 2A of the substrate 100. The plurality ofsecond wirings 400-1, 400-2, . . . may be spaced apart from each otherby a predetermined space. The second wiring unit 400 including theplurality of second wirings 400-1, 400-2, . . . may refer to the secondwiring unit 400 including the first power wiring unit 410, the secondpower wiring unit 420, and the driving circuit wiring unit 430. In otherwords, the first power wiring unit 410, the second power wiring unit420, or the driving circuit wiring unit 430 may each include a pluralityof second wirings 400-1, 400-2, . . . . Thus, the plurality of secondwirings 400-1, 400-2, . . . may refer to a plurality of wirings includedin each of the first power wiring units 410, the second power wiringunits 420 or the driving circuit wiring unit 430.

According to an exemplary embodiment of the present invention, spacesbetween the plurality of second wirings 400-1, 400-2, . . . may begreater than spaces between the plurality of first wirings 300-1, 300-2,. . . in at least some areas. Spaces between the plurality of secondwirings 400-1, 400-2, . . . may refer to spaces between two adjacentsecond wirings 400-1, 400-2, . . . . The second wirings 400-1, 400-2, .. . will be described in more detail below with reference to FIG. 3.

FIG. 3 is a schematic enlarged plan view of a part of a display deviceof FIG. 1.

FIG. 3 schematically illustrates enlarged parts of the first wiring unit300 and the second wiring unit 400 in the bending area BA. The pluralityof second wirings 400-1, 400-2, . . . shown in FIG. 3 may be wirings ofthe first power wiring unit 410, wirings of the second power wiringunit, or wirings of the driving circuit wiring unit 430. FIG. 3illustrates the two first wirings 300-1 and 300-2 that are most adjacentto each other among the plurality of first wirings 300-1, 300-2, . . .of the first wiring unit 300, and the two second wirings 400-1 and 400-2that are most adjacent to each other among the plurality of secondwirings 400-1, 400-2, . . . of the second wiring unit 400.

Referring to FIG. 3, the first wiring unit 300 may include the firstwirings 300-1 and 300-2 that are most adjacent to each other. The firstwirings 300-1 and 300-2 may respectively extend in one direction alongfirst central axes ax. Each of the first central axes ax1 may cross abending axis BAX. According to an exemplary embodiment of the presentinvention, each of the first central axes ax1 may be perpendicular tothe bending axis BAX. For example, the bending axis BAX may be formed inan X axis direction, and the first central axes ax1 may be formed alonga Y axis direction perpendicular to the X axis. According to anexemplary embodiment of the present invention, the first central axesax1 may be formed in a diagonal direction crossing the X axis.

The second wiring unit 400 may include the second wirings 400-1 and400-2 that are most adjacent to each other. The second wirings 400-1 and400-2 may respectively extend in one direction along second central axesax2. Each of the second central axes ax2 may cross the bending axis BAX.According to an exemplary embodiment of the present invention, each ofthe second central axes ax2 may be perpendicular to the bending axisBAX. For example, the bending axis BAX may be formed in the X axisdirection, and the second central axes ax2 may be formed along the Yaxis direction perpendicular to an X axis. According to an exemplaryembodiment of the present invention, the second central axes ax2 may beformed in a diagonal direction crossing the X axis.

Referring to FIG. 3, the first wirings 300-1 and 300-2 and the secondwirings 400-1 and 400-2 may be substantially parallel with each other insome areas. The first wirings 300-1 and 300-2 and the second wirings400-1 and 400-2 may sequentially extend over the first area 1A, thebending BA, and the second area 2A of the substrate 100. The firstwirings 300-1 and 300-2 and the second wirings 400-1 and 400-2 may besubstantially parallel with each other in the bending area BA.

According to an exemplary embodiment of the present invention, the firstcentral axes ax1 included in the first wirings 300-1 and 300-2 may bespaced apart from each other by a first pitch P1, and the second centralaxes ax2 included in the second wirings 400-1 and 400-2 may be spacedapart from each other by a second pitch P2. The first central axis ax1may be an axis extending from centers of one side end and another sideend of each of the first wirings 300-1 and 300-2 in a width direction. Alocation of the first central axis ax may be changed according to apitch P1 between the first wirings 300-1 and 300-2. The pitch P1 will bedescribed in more detail below. The second central axis ax2 may besimilarly positioned. A second pitch P2 may be greater than the firstpitch P1. That is, the plurality of second wirings 400-1 and 400-2 maybe spaced apart from each other by a pitch greater than the firstwirings 300-1 and 300-2. The first pitch P1 may refer to a distancebetween the first central axes ax1 of the first wirings 300-1 and 300-2that are most adjacent to each other. The second pitch P2 may refer to adistance between the second central axes ax2 of the second wirings 400-1and 400-2 that are most adjacent to each other.

According to an exemplary embodiment of the present invention, thesecond pitch P2 may be a times (e.g., n≥2) of the first pitch P. Thesecond pitch P2 of the second wirings 400-1 and 400-2 may increase by amultiple of the first pitch P1 of the first wirings 300-1 and 300-2 andmay increase by a multiple of a natural number except 1. When the secondpitch P2 is n times (e.g., n≥2, 2 is a natural number) of the firstpitch P1, the uniformity of wirings disposed over the substrate 100 maybe increased, thus reducing or eliminating a critical dimension (CD)deviation between the wirings and simultaneously increasingproductivity.

According to an exemplary embodiment of the present invention, thesecond pitch P2 may be 2 times or more the first pitch P. The secondpitch P2 of the second wirings 400-1 and 400-2 may be 2 times or morethe first pitch P1 of the first wirings 300-1 and 300-2 and need notincrease by a multiple of the first pitch P1. In other words, the secondpitch P2 of the second wirings 400-1 and 400-2 may be 2*a (e.g., a≥1) ofthe first pitch P1 of the first wirings 300-1 and 300-2 and “a” may be arational number equal to or greater than 1. When the second pitch P2 is2 times or more the first pitch P1, wirings may be disposed over thesubstrate 100.

According to an exemplary embodiment of the present invention, each ofthe first wirings 300-1 and 300-2 may have a first width w, and each ofthe second wirings 400-1 and 400-2 may have a second width w2. A widthmay be a thickness (width) recognizable on a plane (e.g., an X-Y plane)and may refer to a distance from one side end of a wiring to anotherside end of the wiring in relation to a central axis of the wiring. Thewidth may refer to the distance from one side end of a wiring to anotherside end of the wiring along a width direction of the wiring. Accordingto an exemplary embodiment of the present invention, the second width w2of each of the second wirings 400-1 and 400-2 may be greater than thefirst width w1 of each of the first wirings 300-1 and 300-2. When viewedin a plan view, each of the second wirings 400-1 and 400-2 may bethicker than each of the first wirings 300-1 and 300-2. The second widthw2 of each of the second wirings 400-1 and 400-2 may be greater than thefirst width w1 of each of the first wirings 300-1 and 300-2, and thusthe second pitch P2 of the second wirings 400-1 and 400-2 may be greaterthan the first pitch P of the first wirings 300-1 and 300-2.

The second width w2 of each of the second wirings 400-1 and 400-2 may begreater than the first width w1 of each of the first wirings 300-1 and300-2, and thus the resistance of each of the second wirings 400-1 and400-2 may be less than the resistance of each of the first wirings 300-1and 300-2. The second wiring unit 400 may include a power wiring unitand a driving circuit wiring unit, and thus the resistance of the secondwiring unit 400 may be reduced, thus providing power and driving signalsto each pixel of a display and accordingly increasing the quality of thedisplay.

According to an exemplary embodiment of the present invention, the firstwirings 300-1 and 300-2 may be spaced apart from each other by a firstdistance d1, and the second wirings 400-1 and 400-2 may be spaced apartfrom each other by a second distance d2. The first wirings 300-1 and300-2 may be spaced apart from each other by the first distance d1 and adistance between facing edges of each of the first wirings 300-1 and300-2 that are most adjacent to each other may be the first distance d1.This may also apply to the second wirings 400-1 and 400-2 that arespaced apart from each other by the second distance d2.

The first distance d1 and the second distance d2 may be substantiallythe same. The second distance d2 between the second wirings 400-1 and400-2 may be substantially the same as the first distance d1 between thefirst wirings 300-1 and 300-2. Even if a width of each of the secondwirings 400-1 and 400-2 increases, a minimum distance between the secondwirings 400-1 and 400-2 may be maintained and thus shorts betweenwirings may be reduced or eliminated.

The substrate 100 may be bent along the bending axis BAX in the bendingarea BA, and thus tensile stress may be applied to the plurality offirst wirings 300-1, 300-2, . . . and the plurality of second wirings400-1, 400-2, . . . in the bending area BA. In this case, the firstwiring unit 300 including data wirings may include a relatively largenumber of channels, and the second wiring unit 400 including the powerwiring unit and the driving circuit wiring unit may include relativelyfewer channels than the first wiring unit 300. Thus, the substrate 100may be bent in the bending area BA, thus repeatedly and continuouslyapplying tensile stress to the first wiring unit 300 and the secondwiring unit 400. Bending of the substrate 100 in the bending area BA maycauses cracks or defects due to disconnections in the plurality of firstwirings 300-1, 300-2, . . . of the first wiring unit 300 and theplurality of second wirings 400-1, 400-2, . . . of the second wiringunit 400.

Since the second wiring unit 400 may include relatively fewer channelsthan the first wiring unit 300, a disconnection of one wiring of thesecond wiring unit 400 may be relatively more likely to cause a fataldefect. Since the second wiring unit 400 includes the power wiring unitand the driving circuit wiring unit, when a defect or a disconnectionoccurs in a power wiring or a driving circuit wiring, there may be afatal defect where power is not supplied to the display or a signal isnot applied to a driving signal for driving the display.

The display device 1 according to an exemplary embodiment of the presentinvention may have a pitch between the plurality of second wirings400-1, 400-2, . . . of the second wiring unit 400 greater than a pitchbetween the plurality of first wirings 300-1, 300-2, . . . of the firstwiring unit 300. The second pitch P2 between the plurality of secondwirings 400-1, 400-2, . . . may be greater than the first pitch Pbetween the plurality of first wirings 300-1, 300-2, . . . , thusreducing tensile stress applied to the second wiring unit 400 in thebending area BA of the substrate 100.

FIG. 4 is a schematic enlarged plan view of a part of a display deviceaccording to another exemplary embodiment of the present invention. Adisplay device 2 is described in more detail below with reference toFIG. 4.

FIG. 4 schematically illustrates enlarged parts of the first wiring unit300 and the second wiring unit 400 in the bending area BA. The secondwirings 400-1 and 400-2 shown in FIG. 4 may be wirings of the firstpower wiring unit 410 of the second wiring unit 400, wirings of thesecond power wiring unit 420 thereof, or wirings of the driving circuitwiring unit 430. FIG. 4 illustrates the two first wirings 300-1 and300-2 that are most adjacent to each other among the plurality of firstwirings 300-1, 300-2, . . . of the first wiring unit 300, and the twosecond wirings 400-1 and 400-2 that are most adjacent to each otheramong the plurality of second wirings 400-1, 400-2, . . . of the secondwiring unit 400.

Referring to FIG. 4, the first wirings 300-1 and 300-2 of the firstwiring unit 300 and the second wirings 400-1 and 400-2 of the secondwiring unit 400 may have shapes patterned on a plane. The first wirings300-1 and 300-2 of the first wiring unit 300 and the second wirings400-1 and 400-2 of the second wiring unit 400 may have a chain shape inwhich straight lines and curves cross and are connected to each other.The patterned first wirings 300-1 and 300-2 or second wirings 400-1 and400-2 may be formed by making a plurality of through holes 300 h and 400h having a fan shape alternately facing each other and making outerlines of wirings repeatedly along curves of the through holes 300 h and400 h. However, exemplary embodiments of the present invention are notlimited thereto. The plurality of through holes 300 h and 400 h may havevarious shapes such as a round shape of a fan-shaped cusp, an ovalshape, a circular shape, or a polygonal shape, other than the fan shape.

Such a patterned shape may be selectively applied to only the firstwiring unit 300 and the second wiring unit 400 in the bending area BAand, as another embodiment, may applied to substantially the entiresurface of the substrate 100 including the bending area BA. Thepatterned shape of wirings may distribute tensile stress applied to thewirings in the bending area BA.

The first wiring unit 300 may include the first wirings 300-1 and 300-2.The first wirings 300-1 and 300-2 may respectively extend in onedirection along the first central axes ax1. The second wiring unit 400may include the second wirings 400-1 and 400-2. The second wirings 400-1and 400-2 may respectively extend in one direction along the secondcentral axes ax2. Each of the first central axes ax1 and the secondcentral axes ax2 may cross the bending axis BAX. According to anexemplary embodiment of the present invention, each of the first centralaxes ax land the second central axes ax2 may be perpendicular to thebending axis BAX. For example, the bending axis BAX may be formed in theX axis direction, and the first central axes ax1 and the second centralaxes ax2 may be formed along the Y axis direction perpendicular to the Xaxis. According to an exemplary embodiment of the present invention, thefirst central axes ax1 and the second central axes ax2 may be formed ina diagonal direction crossing the X axis. According to an exemplaryembodiment of the present invention, the first central axes ax and thesecond central axes ax2 may extend along different directions.

Referring to FIG. 4, the first wirings 300-1 and 300-2 and the secondwirings 400-1 and 400-2 may be substantially parallel with each otherand may be disposed in some areas. That is, the first wirings 300-1 and300-2 and the second wirings 400-1 and 400-2 may sequentially extendover the first area 1A, the bending BA, and the second area 2A of thesubstrate 100. The first wirings 300-1 and 300-2 and the second wirings400-1 and 400-2 may be substantially parallel with each other in thebending area BA.

According to an exemplary embodiment of the present invention, the firstcentral axes ax1 included in the first wirings 300-1 and 300-2 may bespaced apart from each other by the first pitch P1, and the secondcentral axes ax2 included in the second wirings 400-1 and 400-2 may bespaced apart from each other by the second pitch P2. The first centralaxis ax1 is an axis extending from centers of one side end and anotherside end of each of the first wirings 300-1 and 300-2 in a widthdirection. A location of the first central axis ax1 may be changedaccording to a pitch between the first wirings 300-1 and 300-2.Referring to FIG. 4, when outer lines of the plurality of first wirings300-1, 300-2, . . . have repetitive curved shapes, the centers of oneside end and another side end of each of the first wirings 300-1 and300-2 in the width direction may be centers of a protrusion from oneside and a protrusion from another side. This may also apply to thesecond central axis ax2.

The second pitch P2 may be greater than the first pitch P1. Theplurality of second wirings 400-1 and 400-2 may be spaced apart fromeach other by a pitch greater than the first wirings 300-1 and 300-2.The first pitch P1 may refer to a distance between the first centralaxes ax1 of the first wirings 300-1 and 300-2 that are most adjacent toeach other. The second pitch P2 may refer to a distance between thesecond central axes ax2 of the second wirings 400-1 and 400-2 that aremost adjacent to each other.

According to an exemplary embodiment of the present invention, thesecond pitch P2 may be n times (e.g., n≥2) of the first pitch P. Thesecond pitch P2 of the second wirings 400-1 and 400-2 may increase by amultiple of the first pitch P1 of the first wirings 300-1 and 300-2 andmay increase by a multiple of a natural number except 1. According to anexemplary embodiment of the present invention, the second pitch P2 maybe 2 times or more the first pitch P1. The second pitch P2 of the secondwirings 400-1 and 400-2 may be 2 times or more the first pitch P1 of thefirst wirings 300-1 and 300-2 and need not increase by a multiple of thefirst pitch P1. The second pitch P2 of the second wirings 400-1 and400-2 may be 2*a (e.g., a≥1) of the first pitch P1 of the first wirings300-1 and 300-2 and “a” may be a rational number equal to or greaterthan 1. Thus, wirings may be disposed over the substrate 100.

According to an exemplary embodiment of the present invention, each ofthe first wirings 300-1 and 300-2 may have the first width w1, and eachof the second wirings 400-1 and 400-2 may have the second width w2. Awidth may be a thickness on a plane (e.g., the X-Y plane) and may referto a distance from one side end of a wiring to another side end of thewiring in relation to a central axis of the wiring. The second width w2of each of the second wirings 400-1 and 400-2 may be greater than thefirst width w1 of each of the first wirings 300-1 and 300-2. When viewedin a plan view, each of the second wirings 400-1 and 400-2 may bethicker than each of the first wirings 300-1 and 300-2. The second widthw2 of each of the second wirings 400-1 and 400-2 may be greater than thefirst width w1 of each of the first wirings 300-1 and 300-2, and thusthe second pitch P2 of the second wirings 400-1 and 400-2 may be greaterthan the first pitch P1 of the first wirings 300-1 and 300-2.

The second width w2 of each of the second wirings 400-1 and 400-2 may begreater than the first width w1 of each of the first wirings 300-1 and300-2, and thus the resistance of each of the second wirings 400-1 and400-2 may be less than the resistance of each of the first wirings 300-1and 300-2. The second wiring unit 400 may include a power wiring unitand a driving circuit wiring unit, and thus the resistance of the secondwiring unit 400 may be reduced, thus providing power and driving signalsto each pixel of a display and accordingly increasing the quality of thedisplay.

According to an exemplary embodiment of the present invention, the firstwirings 300-1 and 300-2 may be spaced apart from each other by the firstdistance d1, and the second wirings 400-1 and 400-2 may be spaced apartfrom each other by the second distance d2. The first wirings 300-1 and300-2 may be spaced apart from each other by the first distance d1,which may refer to a distance between facing edges of each of the firstwirings 300-1 and 300-2 that are most adjacent to each other. This mayalso apply to the second wirings 400-1 and 400-2 that are spaced apartfrom each other by the second distance d2.

The first distance d1 and the second distance d2 may be substantiallythe same. The second distance d2 between the second wirings 400-1 and400-2 may be substantially the same as the first distance d1 between thefirst wirings 300-1 and 300-2. Even if a width of each of the secondwirings 400-1 and 400-2 increases, a minimum distance between the secondwirings 400-1 and 400-2 may be maintained. Thus, shorts between wiringsmay be reduced or eliminated.

FIG. 5 is a schematic enlarged plan view of a part of a display deviceaccording to another exemplary embodiment of the present invention. FIG.6 is a schematic enlarged plan view of a part of a display deviceaccording to another exemplary embodiment of the present invention.FIGS. 5 and 6 schematically illustrate enlarged parts of the firstwiring unit 300 and the second wiring unit 400 in the bending area BA.

Referring to FIG. 5, the first wiring unit 300 may include the firstwirings 300-1 and 300-2. The first wirings 300-1 and 300-2 mayrespectively extend in one direction along the first central axes ax1.The second wiring unit 400 may include the second wirings 400-1 and400-2. The second wirings 400-1 and 400-2 may respectively extend in onedirection along the second central axes ax2. Each of the first centralaxes ax1 and the second central axes ax2 may cross the bending axis BAX.According to an exemplary embodiment of the present invention, each ofthe first central axes ax1 and the second central axes ax2 may beperpendicular to the bending axis BAX. The bending axis BAX may beformed in the X axis direction, and the first central axes ax1 and thesecond central axes ax2 may be formed along the Y axis directionperpendicular to the X axis. According to an exemplary embodiment of thepresent invention, the first central axes ax1 and the second centralaxes ax2 may be formed in a diagonal direction crossing the X axis.

Each of the second central axes ax2 may be located along the directioncrossing the bending axis BAX. According to an exemplary embodiment ofthe present invention, each of the second central axes ax2 may beperpendicular to the bending axis BAX. For example, the bending axis BAXmay be formed in the X axis direction, and the second central axes ax2may be formed along the Y axis direction perpendicular to the X axis.According to an exemplary embodiment of the present invention, thesecond central axes ax2 may be formed in a diagonal direction crossingthe X axis. The first central axes ax1 and the second central axes ax2may extend in different directions.

Referring to FIG. 5, the first wirings 300-1 and 300-2 and the secondwirings 400-1 and 400-2 may be substantially parallel with each other insome areas. That is, the first wirings 300-1 and 300-2 and the secondwirings 400-1 and 400-2 may sequentially extend over the first area 1A,the bending BA, and the second area 2A of the substrate 100. The firstwirings 300-1 and 300-2 and the second wirings 400-1 and 400-2 may besubstantially parallel with each other in the bending area BA.

According to an exemplary embodiment of the present invention, each ofthe second wirings 400-1 and 400-2 may include a first sub wiring 400-1a and a second sub wiring 400-1 b that are electrically connected toeach other. The first sub wiring 400-1 a and the second sub wiring 400-1b may be spaced apart from each by a predetermined space, and thus thefirst sub wiring 400-1 a and the second sub wiring 400-1 b may beconnected in parallel to each other. The first sub wiring 400-1 a andthe second sub wiring 400-1 b may be positioned only in the bending areaBA and might not extend over the first area 1A and the second area 2A inrelation to the bending area BA. For example, the second wiring 400-1may include the first sub wiring 400-1 a and the second sub wiring 400-1b in the bending area, and the second wiring 400-1 may be a singlewiring in the first area 1A and the second area A2. A distance d21between the first sub wiring 400-1 a and the second sub wiring 400-1 bmay be substantially the same as a distance between the first wirings300-1 and 300-2 but exemplary embodiments of the present invention arenot limited thereto. The distance d21 between the first sub wiring 400-1a and the second sub wiring 400-1 b may refer to a distance betweenfacing edges of each of the sub wirings that are most adjacent to eachother among a plurality of sub wirings 400-1 a, 400-2 a.

According to an exemplary embodiment of the present invention, each ofthe second wirings 400-1 and 400-2 may include the plurality of subwirings 400-1 a, 400-1 b, . . . in the bending area BA. The plurality ofsub wirings 400-1 a, 400-1 b, . . . may be combined as a single wiringin the first area 1A and the second area 2A. That is, each of the firstsub wiring 400-1 a and the second sub wiring 400-1 b may have a singlewiring shape like the first wirings 300-1 and 300-2 in the first area 1Aand the second area 2A and then may split into several wirings in thebending area BA. Thus, tensile stress of the second wiring unit 400positioned in the bending area BA may be reduced and resistance of thesecond wiring unit 400 may be reduced through a parallel connection ofthe plurality of sub wirings 400-1 a, 400-1 b, . . . .

According to an exemplary embodiment of the present invention, the firstcentral axes ax1 included in the first wirings 300-1 and 300-2 may bespaced apart from each other by the first pitch P1, and the secondcentral axes ax2 included in the second wirings 400-1 and 400-2 may bespaced apart from each other by the second pitch P2. The second pitch P2may be greater than the first pitch P1. The plurality of second wirings400-1 and 400-2 may be spaced apart from each other by a pitch greaterthan the first wirings 300-1 and 300-2. The first pitch P may refer to aspace between the first central axes ax1 of the first wirings 300-1 and300-2 that are most adjacent to each other. The second pitch P2 mayrefer to a space between the second central axes ax2 of the secondwirings 400-1 and 400-2 that are most adjacent to each other.

According to an exemplary embodiment of the present invention, thesecond pitch P2 may be n times (e.g., n≥2) of the first pitch P1. Thatis, the second pitch P2 of the second wirings 400-1 and 400-2 mayincrease by a multiple of the first pitch P1 of the first wirings 300-1and 300-2 and may increase by a multiple of a natural number except 1.

According to an exemplary embodiment of the present invention, thesecond pitch P2 may be 2 times or more the first pitch P1. That is, thesecond pitch P2 of the second wirings 400-1 and 400-2 may be 2 times ormore the first pitch P of the first wirings 300-1 and 300-2 and need notincrease by a multiple of the first pitch P1. The second pitch P2 of thesecond wirings 400-1 and 400-2 may be 2*a (e.g., a≥1) of the first pitchP1 of the first wirings 300-1 and 300-2 and “a” may be a rational numberequal to or greater than 1. Thus, wirings may be disposed over thesubstrate 100.

According to an exemplary embodiment of the present invention, each ofthe first wirings 300-1 and 300-2 may have the first width w1, and eachof the second wirings 400-1 and 400-2 may have the second width w2. Awidth may be a thickness recognizable on a plane (e.g., the X-Y plane)and may refer to a distance from one side end of a wiring to anotherside end of the wire in relation to a central axis of the wiring. Thesecond width w2 of each of the second wirings 400-1 and 400-2 may begreater than the first width w1 of each of the first wirings 300-1 and300-2.

Each of the second wirings 400-1 and 400-2 may be may include multiplesub wirings, and thus the second width w2 of each of the second wirings400-1 and 400-2 may be greater than the first width w1 of each of thefirst wirings 300-1 and 300-2 formed in a single line. The second widthw2 of each of the second wirings 400-1 and 400-2 may be greater than thefirst width w1 of each of the first wirings 300-1 and 300-2, and thusthe second pitch P2 of the second wirings 400-1 and 400-2 may be greaterthan the first pitch P1 of the first wirings 300-1 and 300-2.

Each of the second wirings 400-1 and 400-2 may include sub wirings,which may increase the second pitch P2 of the second wirings 400-1 and400-2. The sub wirings may be electrically connected in parallel to eachother, and thus the resistance of each of the second wirings 400-1 and400-2 may be less than the resistance of each of the first wirings 300-1and 300-2. The second wiring unit 400 may include a power wiring unitand a driving circuit wiring unit, and thus the resistance of the secondwiring unit 400 may be reduced, thus providing power and driving signalsto each pixel of a display and accordingly increasing the quality of thedisplay.

According to an exemplary embodiment of the present invention, the firstwirings 300-1 and 300-2 may be spaced apart from each other by the firstdistance d1, and the second wirings 400-1 and 400-2 may be spaced apartfrom each other by the second distance d2. The first wirings 300-1 and300-2 may be spaced apart from each other by the first distance d1, andd1 may refer to a distance between facing edges of each of two wiringsthat are most adjacent to each other among the plurality of the firstwirings 300-1, 300-2, . . . . This may also apply to the second wirings400-1 and 400-2 that are spaced apart from each other by the seconddistance d2. In case of the second wirings 400-1 and 400-2, a distancebetween facing edges of each of two wirings that are most adjacent toeach other among the plurality of the second wirings 400-1, 400-2, . . .is the second distance d2.

The first distance d1 and the second distance d2 may be substantiallythe same. The second distance d2 between the second wirings 400-1 and400-2 may be substantially the same as the first distance d1 between thefirst wirings 300-1 and 300-2. Even if a width of each of the secondwirings 400-1 and 400-2 increases, a minimum distance between the secondwirings 400-1 and 400-2 may be maintained, thus reducing or eliminatingshorts between wirings.

FIG. 6 is a schematic enlarged plan view of a part of a display deviceaccording to another exemplary embodiment of the present invention. FIG.6 illustrates a modification of an exemplary embodiment of the presentinvention described with reference to FIG. 5 and is different from theexemplary embodiment of the present invention described with referenceto FIG. 5 in a shape of the second wiring unit 400. The exemplaryembodiment of the present invention described with reference to FIG. 6may be substantially the same as the exemplary embodiment of the presentinvention described with reference to FIG. 5 except for the shape of thesecond wiring unit 400, and thus redundant descriptions may be omitted.

Referring to FIG. 6, a shape of each of the second wirings 400-1 and400-2 of the second wiring unit 400 may include a third sub wiring 400-1c. Each of the second wirings 400-1 and 400-2 may include the first subwiring 400-1 a, the second sub wring 400-1 b, and the third sub wiring400-1 c.

The first central axes ax1 included in the first wirings 300-1 and 300-2may be spaced apart from each other by the first pitch P1, and thesecond central axes ax2 included in the second wirings 400-1 and 400-2may be spaced apart from each other by the second pitch P2. The secondpitch P2 may be greater than the first pitch P1. The plurality of secondwirings 400-1 and 400-2 may be spaced apart from each other by a pitchgreater than the first wirings 300-1 and 300-2.

The third sub wiring 400-1 c may be added compared to the exemplaryembodiment of the present invention described with reference to FIG. 5,and thus the second pitch P2 between the second wirings 400-1 and 400-2may be increased. Sub wirings may be added to each of the second wirings400-1 and 400-2, and thus a width of the second pitch P2 may beincreased. Sub wirings that are connected in parallel to each other maybe added, and thus the resistance of the second wiring unit 400 may berelatively lower than resistance of the first wiring unit 300. Accordingto an exemplary embodiment of the present invention, the first wirings300-1 and 300-2 may be spaced apart from each other by the firstdistance d1, and the second wirings 400-1 and 400-2 may be spaced apartfrom each other by the second distance d2 that is substantially the sameas the first distance d1.

The distance d21 between the first sub wiring 400-1 a and the second subwiring 400-1 b may be substantially the same as a distance between thefirst wirings 300-1 and 300-2 but exemplary embodiments of the presentinvention are not limited thereto. A distance d22 between the second subwiring 400-1 b and the third sub wiring 400-1 c may be substantially thesame as the distance between the first wirings 300-1 and 300-2 butexemplary embodiments of the present invention are not limited thereto.The distance d2 l between the first sub wiring 400-1 a and the secondsub wiring 400-1 b may be substantially the same as the distance d22between the second sub wiring 400-1 b and the third sub wiring 400-1 cbut exemplary embodiments of the present invention are not limitedthereto. The distance d21 between the first sub wiring 400-1 a and thesecond sub wiring 400-1 b and the distance d22 between the second subwiring 400-1 b and the third sub wiring 400-1 c may refer to a distancebetween facing edges of each of wrings that are most adjacent to eachother among the plurality of sub wirings 400-1 a, 400-2 a, . . . .

The substrate 100 may be bent along the bending axis BAX in the bendingarea BA, and thus tensile stress may be applied to the plurality offirst wirings 300-1, 300-2, . . . and the plurality of second wirings400-1, 400-2, . . . in the bending area BA. The first wiring unit 300including data wirings may include a relatively large number ofchannels. The second wiring unit 400 including the power wiring unit andthe driving circuit wiring unit may include relatively fewer channelsthan the first wiring unit 300. Thus, the substrate 100 may be bent inthe bending area BA, and tensile stress may be applied to the firstwiring unit 300 and the second wiring unit 400, which may cause cracksor defects due to disconnections in the plurality of first wirings300-1, 300-2, . . . of the first wiring unit 300 and the plurality ofsecond wirings 400-1, 400-2, . . . of the second wiring unit 400.

Since the second wiring unit 400 may include relatively fewer channelsthan the first wiring unit 300, a disconnection of one wiring may resultin a fatal defect in the display. Since the second wiring unit 400includes the power wiring unit and the driving circuit wiring unit, whena defect or a disconnection occurs in a power wiring or a drivingcircuit wiring, there may be a fatal defect where power is not suppliedto the display or a signal is not applied to a driving signal fordriving the display.

The display device according to an exemplary embodiment of the presentinvention may have a pitch between the plurality of second wirings400-1, 400-2, . . . of the second wiring unit 400 greater than a pitchbetween the plurality of first wirings 300-1, 300-2, . . . of the firstwiring unit 300. The second pitch P2 between the plurality of secondwirings 400-1, 400-2, . . . may be greater than the first pitch P1between the plurality of first wirings 300-1, 300-2, . . . , which mayreduce a tensile stress applied to the second wiring unit 400 in thebending area BA of the substrate 100.

FIG. 7 is a cross-sectional view of a part of the display device of FIG.1.

FIG. 7 illustrates a pixel structure of the display 200 included in thedisplay device described with reference to FIG. 1. Although an organiclight-emitting device (OLED) is employed as a display device 250 of thedisplay 200, according to another exemplary embodiment of the presentinvention, an inorganic light-emitting device such as a liquid crystaldevice or an inorganic light-emitting device ILED may be employed.

The display 200 may include a thin film transistor TFT to which thedisplay device 250 is electrically connected, in addition to the displaydevice 250. The OLED may be disposed in the display 200 as the displaydevice 250. Electrically connecting the OLED to the thin film transistorTFT may include electrically connecting a pixel electrode 220 to thethin film transistor TFT. The thin film transistor TFT may be disposedin the non-display area NDA outside the display area DA of the substrate100. The thin film transistor TFT disposed in the non-display area NDAmay be, for example, a part of a circuit unit for controlling anelectrical signal applied to the display 200.

A buffer layer 201 including a silicon oxide, or a silicon nitride, forexample, may be disposed over the substrate 100. A semiconductor layer202 may be disposed on the buffer layer 201. The buffer layer 201 mayplanarize a surface of the substrate 100 or may reduce or preventimpurities from penetrating into the semiconductor layer 202 of the thinfilm transistor TFT.

A gate electrode 204 may be disposed over the semiconductor layer 202. Asource electrode 206 a and a drain electrode 206 b may be electricallyconnected to each other according to a signal applied to the gateelectrode 204. The gate electrode 204 may include one or more materialsof, for example, aluminum (Al), platinum (Pt), palladium (Pd), silver(Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium(Ir), chromium (Cr), calcium (Ca), molybdenum (Mo), titanium (Ti),tungsten (W), and copper (Cu) in a single-layered or multi-layeredstructure, in consideration of adhesion to adjacent layers, surfacesmoothness of stacked layers, and processability.

A gate insulating layer 203 including a silicon oxide and/or a siliconnitride may be disposed between the semiconductor layer 202 and the gateelectrode 204. The gate insulating layer 203 may insulate thesemiconductor layer 202 and the gate electrode 204 from each other.

An interlayer insulating layer 205 may be disposed above the gateelectrode 204 and may include a silicon oxide, or a silicon nitride, forexample, in a single-layered or multi-layered structure.

The source electrode 206 a and the drain electrode 206 b may be disposedon the interlayer insulating layer 205. The source electrode 206 a andthe drain electrode 206 b may be electrically connected to thesemiconductor layer 202 via respective contact holes formed in both ofthe interlayer insulating layer 205 and the gate insulating layer 203.The source electrode 206 a and the drain electrode 206 b may include oneor more materials of, for example, aluminum (Al), platinum (Pt),palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni),neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), molybdenum(Mo), titanium (Ti), tungsten (W), and copper (Cu) in a single-layeredor multi-layered structure, in consideration of conductivity or thelike.

A protective layer may cover the thin film transistor TFT and mayprotect the thin film transistor TFT. The protective layer may includean inorganic material such as silicon oxide, silicon nitride, or siliconoxynitride.

A planarization layer 207 may be disposed over the substrate 100. Theplanarization layer 207 may be a protective layer. When an OLED isdisposed over the thin film transistor TFT, the planarization layer 207may generally planarize an upper surface of the thin film transistor TFTand protect the thin film transistor TFT and various devices. Theplanarization layer 207 may include, for example, an acryl-based organicmaterial, or benzocyclobutene (BCB). The buffer layer 201, the gateinsulating layer 203, the interlayer insulating layer 205, and theplanarization layer 207 may be formed over substantially the entiresurface of the substrate 100.

A pixel defining layer 208 may be disposed above the thin filmtransistor TFT. The pixel defining layer 208 may be disposed onplanarization layer 207 and may have an aperture. The pixel defininglayer 208 may define a pixel area on the substrate 100.

The pixel defining layer 208 may include, for example, an organicinsulating layer. The organic insulating layer may include anacryl-based polymer such as polymethyl methacrylate (PMMA), polystyrene(PS), a polymer derivative having a phenol group, an imide-basedpolymer, an acryl ether-based polymer, an amide-based polymer, afluorine-based polymer, a p-xylene-based polymer, a vinyl alcohol-basedpolymer, or a mixture of these materials.

The display device 250 may be disposed above the planarization layer207. The display device 250 may include the pixel electrode 220, anintermediate layer 230 including an emission layer (EML), and anopposite electrode 240.

The pixel electrode 220 may include a transparent (or semi-transparent)electrode or a reflective electrode. When the pixel electrode 220includes the transparent (or semi-transparent) electrode, the pixelelectrode 220 may include, for example, indium tin oxide (ITO), indiumzinc oxide (IZO), zinc oxide (ZnO), indium oxide (In₂O₃), indium galliumoxide (IGO), or aluminum zinc oxide (AZO). When the pixel electrode 220includes the reflective electrode, the pixel electrode 220 may include areflective layer including silver (Ag), magnesium (Mg), aluminum (A),platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium (Nd),iridium (Ir), chromium (Cr), or a combination thereof, and a layerincluding ITO, IZO, ZnO, In₂O₃, IGO, or AZO. However, exemplaryembodiments of the present invention are not limited thereto. The pixelelectrode 220 may include various other materials and may have variousother structures, such as, a single-layered or multi-layered structure.

The intermediate layer 230 may be disposed in the pixel area defined bythe pixel defining layer 208. The intermediate layer 230 may include theemission layer (EML) emitting light according to an electrical signal,and may include a hole injection layer (HIL) and a hole transport layer(HTL), an electron transport layer (ETL) disposed between the EML andthe pixel electrode 220, and an electron injection layer (EIL) betweenthe EML and the opposite electrode 240, in a single or complex stackstructure but exemplary embodiments of the present invention are notlimited thereto. The intermediate layer 230 may have various otherstructures.

The opposite electrode 240 that covers the intermediate layer 230including the EML and faces the pixel electrode 220 may be disposed oversubstantially the entire surface of the substrate 100. The oppositeelectrode 240 may include a transparent (or semi-transparent) electrodeor a reflective electrode.

When the opposite electrode 240 includes the transparent (orsemi-transparent) electrode, the opposite electrode 240 may include alayer including a metal having a relatively small work function, forexample, Li, Ca, LiF/Ca, LiF/Al, Al, Ag, Mg, or a combination thereof,and a transparent (or semi-transparent) conductive layer including ITO,IZO, ZnO, or In₂O₃. When the opposite electrode 240 includes thereflective electrode, the opposite electrode 240 may include a layerincluding Li, Ca, LiF/Ca, LiF/Al, Al, Ag, Mg, or a combination thereof.The configuration and materials of the opposite electrode 240 are notlimited to those described herein, and may have various modifications.

According to some exemplary embodiments of the present invention,functional layers, such as an encapsulation layer, a polarization layer,and a color filter, may be disposed above the opposite electrode 240.

FIG. 8 is a schematic plan view of a part of the display device ofFIG. 1. FIG. 8 illustrates a shape in which the first wiring unit 300and the second wiring unit 400 are disposed in the first area 1A, thebending area BA, and the second area 2A of the substrate 100.

Referring to FIG. 8, the first wiring unit 300 and the second wiringunit 400 in the bending area BA may be substantially the same as thosedescribed above. That is, in the first wiring unit 300 and the secondwiring unit 400 in the bending area BA, the first wiring unit 300 mayhave the first pitch P1 and the second wiring unit 400 may have thesecond pitch P2 greater than the first pitch P1. A width of each of theplurality of second wirings 400-1, 400-2, 400-3, 400-4, . . . may begreater than a width of each of the first wirings 300-1, 300-2, 300-3,300-4, . . . .

The first wiring unit 300 and the second wiring unit 400 that arepositioned in the first area 1A and the second area 2A except for thebending area BA may each respectively have a third pitch P1′ and afourth pitch P2′. The third pitch P1′ and the fourth pitch P2′ may besubstantially the same.

In the second wiring unit 400, the plurality of second wirings 400-1,400-2, 400-3, 400-4, . . . may have the second pitch P2 in the bendingarea BA and the fourth pitch PT in the first area 1A and the second area2A. A change in a pitch of the plurality of second wirings 400-1, 400-2,400-3, 400-4, . . . from the second pitch P2 to the fourth pitch P2′smaller than the second pitch P2, may reduce a width in each of the ofthe plurality of second wirings 400-1, 400-2, 400-3, 400-4, . . . fromthe second width w2 to a fourth width w2′. However, in this case, thedistance d2 between the plurality of second wirings 400-1, 400-2, 400-3,400-4, . . . in the bending area BA may be substantially the same as adistance d2′ between the plurality of second wirings 400-1, 400-2,400-3, 400-4, . . . in the first area 1A and the second area 2A. Thedistances d2 and d2′ between the plurality of second wirings 400-1,400-2, 400-3, 400-4, . . . may refer to distances between facing edgesof each of wirings that are most adjacent to each other among theplurality of second wirings 400-1, 400-2, 400-3, 400-4, . . . .

In the first wiring unit 300, the plurality of first wirings 300-1,300-2, 300-3, 300-4, . . . may have the first pitch P1 in the bendingarea BA and the third pitch P1′ that is substantially the same as thefirst pitch P1 in the first area 1A and the second area 2A. The samepitch between the plurality of first wirings 300-1, 300-2, 300-3, 300-4,. . . in the first area 1A, the bending area BA, and the second area 2Amay refer to the first width w1 being substantially the same as a thirdwidth w1′ of the plurality of first wirings 300-1, 300-2, 300-3, 300-4,. . . .

The second wiring unit 400 may also have substantially the same pitch asthe first wiring unit 300 in the first area 1A and the second area 2Aexcept for the bending area BA. However, a pitch of the second wiringunit 400 may increase from the fourth pitch P2′ to the second pitch P2in the bending area BA and thus a width of each of the plurality ofsecond wirings 400-1, 400-2, 400-3, 400-4, . . . may also increase. Anarea in which the first area 1A and the bending area BA contact eachother and an area in which the second area 2A and the bending area BAcontact each other may broaden or narrow to have a fan-out shape sincethe pitch of the second wiring unit 400 may change.

The second wiring unit 400 may include a same material as the sourceelectrode 206 a or the drain electrode 206 b of the thin film transistorTFT in the entire area of the substrate 100. The first wiring unit 300may include a same material as the gate electrode 300 of the thin filmtransistor TFT in the first area 1A and the second area 2A and mayinclude a same material as the source electrode 206 a or the drainelectrode 206 b of the thin film transistor TFT in the bending area BA.

FIG. 9 is a schematic cross-sectional view taken along a line A-A ofFIG. 8.

FIG. 9 illustrates the non-display area NDA of one side of the display200. The non-display area NDA may include the first area 1A, the bendingarea BA, and the second area 2A. FIG. 9 is a cross-sectional view of thefirst wiring unit 300. The first wiring unit 300 may be one first wiringof the plurality of first wirings 300-1, 300-2, . . . included in thefirst wiring unit 300.

Referring to FIG. 9, the buffer layer 201, the gate insulating layer203, and the interlayer insulating layer 205 that include an inorganicmaterial may be referred to as an inorganic insulating layer. Theinorganic insulating layer may be disposed over substantially the entiresurface of the substrate 100 and may have an aperture corresponding tothe bending area BA. The buffer layer 201, the gate insulating layer203, and the interlayer insulating layer 205 may respectively haveapertures 201 a, 203 a, and 205 a corresponding to the bending area BA.The apertures may overlap the bending area BA. An area of an aperturemay be greater than an area of the bending area BA. A width of theaperture may be greater than a width of the bending area BA. The area ofthe aperture may be defined as an area of an aperture having thesmallest area among the apertures 201 a, 203 a, and 205 a of the bufferlayer 201, the gate insulating layer 203, and the interlayer insulatinglayer 205. Referring to FIG. 8, the area of the aperture may be definedby an area of the aperture 201 a of the buffer layer 201. An innersurface of the aperture 201 a of the buffer layer 201 and an innersurface of the aperture 203 a of the gate insulating layer 203 may esubstantially identical to each other; however, exemplary embodiments ofthe present invention are not limited thereto.

The first wiring unit 300 may be disposed over the first area 1A, thebending area BA, and the second area 2A to cover the apertures 201 a,203 a, and 205 a. The first wiring unit 300 may include a firstconductive layer 300 a and a second conductive layer 300 b. The firstconductive layer 300 a may be positioned in the bending area BA, and thesecond conductive layer 300 b may be positioned in the first area 1A andthe second area 2A. The first conductive layer 300 a and the secondconductive layer 300 b may be electrically connected to each other via acontact hole.

The first conductive layer 300 a may be positioned over the bending areaBA, may cover the apertures 201 a, 203 a, and 205 a and may extend tothe first area 1A and the second area 2A. A part of the substrate 100may be exposed to the outside through the aperture 201 a of the bufferlayer 201 and the aperture 203 a of the gate insulating layer 203, andthus the first conductive layer 300 a may directly contact the substrate100 through the apertures 201 a and 203 a. However, an inorganicinsulating layer or an organic insulating layer may be further disposedbetween the first conductive layer 300 a and the substrate 100.

The second conductive layer 300 b may be positioned in the first area 1Aand the second area 2A. The first conductive layer 300 a and the secondconductive layer 300 b may be insulated by the interlayer insulatinglayer 205 and may be electrically connected through the contact hole.The second conductive layer 300 b may further extend to the first area1A and the second area 2A. The second conductive layer 300 b may bepositioned outside the display area DA and may be electrically connectedto elements positioned in the display area DA. The second conductivelayer 300 b may be positioned outside the display area DA and may extendin a direction of the display area DA and may be at least partiallypositioned in the display area DA.

The first conductive layer 300 a may include a same material as thesource electrode 206 a or the drain electrode 206 b of the thin filmtransistor TFT and may be formed substantially simultaneously with thesource electrode 206 a or the drain electrode 206 b. The secondconductive layer 300 b may include a same material as the gate electrode204 of the thin film transistor TFT and may be formed substantiallysimultaneously with the gate electrode 204. The source electrode 206 aor the drain electrode 206 b of the thin film transistor TFT may includea relatively more flexible metal than the gate electrode 204.

If the first wiring unit 300 does not include the first conductive layer300 a and the second conductive layer 300 b and includes a wiring of asingle layer, maximum tensile stress may be applied to a part of thefirst wiring unit 300 positioned in the bending area BA, and a crack anda disconnection may occur. In the display device according to anexemplary embodiment of the present invention, the first wiring unit 300may include the first conductive layer 300 a and the second conductivelayer 300 b, and the first conductive layer 300 a positioned in thebending area BA may include a same material as the source electrode 206a or the drain electrode 206 b having relatively high flexibility. Thus,the tensile stress applied to the first wiring unit 300 may be reduced.

Referring to FIG. 9, an inorganic insulating layer corresponding to thebending area BA may have an aperture. If the inorganic insulating layeris continuously disposed over the bending area BA, a crack may occur inthe inorganic insulating layer positioned in the bending area BA duringa process of bending the substrate 100 in the bending area BA, which maycause a defect such as a disconnection of the first wiring unit 300positioned over the inorganic insulating layer. In the display deviceaccording to an exemplary embodiment of the present invention, theinorganic insulating layer may overlap with the bending area BA to havean aperture, and the first conductive layer 300 a may be disposed tocover the aperture, thus reducing or eliminating defects in the firstwiring unit 300 due to bending of the substrate 100.

The substrate 100 of the display device according to an exemplaryembodiment of the present invention may be bent in the bending area BA.The display device may be manufactured to have the substrate 100 in anapproximately flat state, and then the display device may be bent bybending the substrate 100 in the bending area BA. Although tensilestress may be applied to the first wiring unit 300 or the second wiringunit 400 during the process of bending the substrate 100 in the bendingarea BA, the display device according to an exemplary embodiment of thepresent invention may reduce or prevent an occurrence of a defect in thefirst wiring unit 300 and the second wiring unit 400.

FIG. 10 is a schematic cross-sectional view of a part of a displaydevice according to another exemplary embodiment of the presentinvention.

The exemplary embodiment of the present invention described withreference to FIG. 10 may be substantially the same as the exemplaryembodiment of the present invention described with reference to FIG. 8except that an organic layer 260 may be disposed between the substrate100 and the first conductive layer 300 a in the bending area BA, andthus redundant descriptions may be omitted.

Referring to FIG. 10, the organic insulating layer 260 may be disposedover the bending area BA, and over parts of the first area 1A and thesecond area 2A. The organic insulating layer 260 may cover an apertureof the inorganic insulating layer. Since the substrate 100 may be bentin the bending area BA, tensile stress may be applied to the firstwiring unit 300 and/or the second wiring unit 400 positioned in thebending area BA. In the display device, the aperture may be formed inthe inorganic insulating layer to correspond to the bending area BA andthen the organic layer 260 may be disposed to cover the aperture, andthe first conductive layer 300 a may be disposed over the organic layer260. Thus, the organic layer 260 disposed in the bending area BA mayeffectively distribute stress applied to the first conductive layer 300a and may reduce or prevent an occurrence of cracks in the firstconductive layer 300 a.

According to an exemplary embodiment of the present invention, an uppersurface of the organic layer 260 may be uneven and may have a wavepattern shape. An uneven structure of the upper surface of the organiclayer 260 may increase a distribution of stress when the bending area BAis bent.

FIG. 1 is a schematic cross-sectional view of a part of a display deviceaccording to another exemplary embodiment of the present invention. FIG.11 is a cross-sectional view of the second wiring unit 400 of FIG. 8taken along a line B-B.

Referring to FIGS. 8 and 11, the buffer layer 201, the gate insulatinglayer 203, and the interlayer insulating layer 205 that are inorganicinsulating layers may respectively have the apertures 201 a, 203 a, and205 a corresponding to the bending area BA. The second wiring unit 400may be disposed over the first area 1A, the bending area BA and thesecond area 2A to cover the apertures 201 a, 203 a, and 205 a. Thesecond wiring unit 400 may include a third conductive layer 400 a. Thethird conductive layer 400 a may include a same material as the secondwiring unit 400 and may be integrally formed with the second wiring unit400.

FIG. 12 is a graph showing bending of a display device according to anexemplary embodiment of the present invention.

The graph of FIG. 12 shows a number of times two samples havingdifferent pitches between wirings are bent before two wirings aredisconnected. The x axis of the graph indicates two wirings havingdifferent pitches, and the Y axis of the graph indicates the number oftimes the wirings are bent.

Referring to FIG. 12, a first sample A is set to have a pitch betweentwo wirings at about 60 μm, and a width of each of the two wirings atabout 48 μm, whereas a second sample B is set to have a pitch betweentwo wirings at about 18 μm, and the width of each of the two wirings atabout 13 μm in the present test. That is, the first sample A is set tohave a pitch and a width that is about 3 times greater than the secondsample B. Forming and bending the first sample A and the second sample Bover a substrate may occur under the same conditions.

Referring to FIG. 12, the two wirings of the first sample A aredisconnected at a 34 times bending, whereas the two wirings of thesecond sample B are disconnected at 25.5 times bending. That is, thefirst sample A that is set to have a pitch between two wirings at about60 μm, and the width of each of the two wirings at about 48 μm isstronger against tensile stress applied when bent than the second sampleB that is set to have a pitch between two wirings at about 18 μm and thewidth of each of the two wirings at about 13 μm. Thus, increased pitchbetween wirings may result in increased bending characteristics and adecrease in separation between wirings.

The display device according to exemplary embodiments of the presentinvention may reduce or eliminate an occurrence of defects, such as adisconnection, during manufacturing of the display device whileincreasing a lifespan of the display device may. However, the scope ofthe exemplary embodiments of the present invention is not restricted bythis effect.

While one or more embodiments have been described with reference to thefigures, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope as defined by the following claims.

What is claimed is:
 1. A display device comprising: a substrateincluding a bending area in which the substrate is bent; a first wiringunit comprising a plurality of first wirings arranged across the bendingarea of the substrate, a second wiring unit comprising a plurality ofsecond wirings arranged across the bending area of the substrate,wherein each of the plurality of first wirings is a single wiring in thebending area, and wherein each of the plurality of second wirings isbranched into a plurality of sub wirings in the bending area.
 2. Thedisplay device of claim 1, wherein the substrate includes a first areaand a second area, and the bending area is located between the firstarea and the second area, wherein each of the plurality of secondwirings is arranged in the first area and the second area as a singlewiring.
 3. The display device of claim 1, wherein each of the pluralityof second wirings comprises a first sub wiring and a second sub wiringthat are spaced apart from each other by a predetermined distance in thebending area, and the first sub wiring and the second sub wiring areelectrically connected to each other.
 4. The display device of claim 3,wherein the first sub wiring and the second sub wiring are connected inparallel to each other.
 5. The display device of claim 3, wherein eachof the plurality of second wirings further comprises a third sub wiringspaced apart from the second sub wiring by a predetermined distance, andwherein the second sub wiring and the third sub wiring are electricallyconnected to each other.
 6. The display device of claim 1, wherein theplurality of sub wirings arranged in the bending area are spaced apartfrom each other by substantially the same distance.
 7. The displaydevice of claim 6, wherein the plurality of first wirings are spacedapart from each other by a first distance, and the plurality of subwirings are spaced apart from each other by a second distance that issubstantially the same as the first distance.
 8. The display device ofclaim 1, Wherein each of the second wirings of the plurality of secondwirings are symmetrical to each other with respect to each of theplurality of second central axes.
 9. The display device of claim 1,further comprising: a display disposed over the substrate; and a driverdisposed around the display and configured to drive the display, whereinthe first wiring unit is a power supply wiring unit is configured tosupply power to the driver or the display, and wherein the second wiringunit is a data signal wiring unit configured to provide a data signal tothe display.
 10. The display device of claim 1, wherein the plurality offirst wirings and the plurality of sub wirings are substantiallyparallel with each Other.
 11. The display device of claim 1, wherein theplurality of first wirings and the plurality of sub wirings extend in adirection crossing the bending axis.
 12. The display device of claim 1,wherein first central axes in each of the plurality of first wirings arespaced apart from each other by a first pitch in the bending area, andwherein second central axes in each of the plurality of second wiringsare spaced apart from each other by a second pitch different from thefirst pitch.
 13. The display device of claim 12, wherein the secondpitch is greater than the first pitch in the bending area.
 14. Thedisplay device of claim 12, wherein the second pitch is n times as wideas the first pitch, wherein n≥2 and n is a natural number.
 15. Thedisplay device of claim 12, wherein the second pitch is at least twiceas wide as the first pitch.
 16. The display device of claim 12, whereinthe plurality of respective second central axes, of the plurality ofsecond wirings are spaced apart from each other by a pitch less than thesecond pitch in, the first area and the second area.
 17. The displaydevice of claim 1, wherein resistance of each of the plurality of secondwirings is less than resistance of each of the plurality of firstwirings.
 18. The display device of claim 1, further comprising a padunit located over the second area of the substrate.
 19. The displaydevice of claim 1, the display device further comprising: a thin filmtransistor including a source electrode, a drain electrode, and a gateelectrode, wherein the second wiring unit comprises a first conductivelayer in the bending area and a second conductive layer in the firstarea and the second area, and wherein the second conductive layercomprises a same material as the source electrode or the drainelectrode, and the second conductive layer comprises a same material asthe gate electrode.
 20. The display device of claim 19, wherein theplurality of sub wirings comprises the first conductive layer.
 21. Thedisplay device of claim 19, wherein the first conductive layer and thesecond conductive layer are electrically connected to each other via acontact hole.